Stylus bar for talking machines



@Cin 2 n F. A. E. JENKINS STYLUS BAR FOR TALKING MACHINES Filed March 271924 Patented Oct. 21, 1924.

UNITED STATES PATENT, OFFICE...

FREDRICK ALFRED EDWARD JENKINS, or SYDNEY, NEW SOUTH WALES, AUSTRALIA.

STYLUS. BAR roe TALKING MACHINES.

Application filled March 27, 19 24. Serial No; 702,467;

To all whom it may concern:

Be it known that FREDRIOK ALFRED En.-

wAR-n JENKINs, a subject of; the King off Great Britain and Ireland,residing at.6 Haig Avenue, Summer. Hill, Sydney, in the State of NewSouth Wales, Commonwealth of Australia, engineer, has invented. certainnew and" useful Improvements in .Stylus' Bars for Talking Machines, ofwhich the following isa specification.

This invention" relates to the method: of mounting-stylus bars;on thesound boxes of. talking machines and has for its object an improvedmeans of attaching-the stylus bar to the sound box whereby thestylusbar, is

permitted to oscillate freelywand convey the.

vibrations imparted to it by the" record to the diaphragm with as littleresistance as possible.

The invention consists in mounting the stylus bar on three pin pointsone of which opposes the other two, the three points being in alignmentwith each other and in the same plane and the line through the threepoints parallel to the plane of the diaphragm. The inventionfurtherconsists in making pin points adjustable so that anyirregularities or imperfections in the stylus may be counteracted.

The invention will be fully explained with reference to the accompanyingdrawings in which Figure 1 is a perspective view of a sound box of thehorizontal type showing the method of attaching the stylus bar accordingto this invention.

Figure 2 is a similar viewl sound box of the vertical type.

Figure 3 is a perspective view of a sound box showing an alternativemethod of carrying out the invention. I

Figure 4 is an enlarged elevation of the alternative method shown inFigure 3, and

of part of a Figure 5 is a perspective view ofa sound A third point 17attached to the stylus bar 16 bears against the projecting arm andopposes the pin points 13 and 14. The points 13;,14and 1 7 are in thesame plane and: in alignmentv with each other and the line throughthe-.pointsis parallel to the plane. of the diaphragm, so that thearms'151 of the stylus-bar are permitted to oscillate freelyand convey thevibrations imparted to the stylus'or needle by the record, with a mini;mum. resistance to the diaphragm. of the sound. box;:.

In the vertical type of sound: box (see ure 2i. the point 17 isattached. to the sound box' (i and the screws: 11. and" 12 projectthrough. small brackets 18 formedv on the sound: box; The stylus bar 16bearsagainst the three points 13,. 14 and: 17 whichaare. in.

the. same plane a and in. alignment. with. each other.. The. point. 17as. beforeopposes' the points 13 and 14 and the line through the pointsis parallel to the plane of the diaphragm.

In the alternative method shown in Figure 3 the point 17 is slidablycontained within a sleeve 19 attached to the sound box and is pressedagainst the stylus bar by a spring 20 the pressure of which may bevaried by the screw 21, the bearing points 13, 14 and 17 being ashereinbefore set out in the same plane and in alignment with each other.As shown in Figure .4 the line A A ofthe pin points 13, 14 and 17 isparallel to the plane of the diaphragm.

In the modification shown in Figure 5 the point 17 and arm-1O arereplaced by a knife edge 22 which bears at right angles on another knifeedge 23 formed in the stylus bar 16. The edge 22 is integral with theplate 24 which is adjustably secured to the sound box 6 by means of thesprings 25 which bear '1. In a talking machine in combination,

a sound box having, a diaphra In, a stylus bar, spaced arms carried byan projecting laterally from the sound box and arranged on oppositesides of the stylus bar, hori-.

zontal arms extending in opposite directions fromthe stylus bar andarranged in proximity to the arms of the sound box, pins mounted throughthe ends of one set of said arms and having pointed ends bearingtransversely and convey the Vibrations i1n-' parted to the stylus withminimum resistaneeito the vdraphragm, the pins being adjustable sons tocounteract irregularities in projecting laterally therefrom,

the stylus bar, and the points of engagement of said pins and bearingmember being arranged 1n the same plane and in alignment W1th each otherso that a line drawn phra'gm of the soundbox;

In a talklngmaehine lnoombination, a sound box having a diaphragm, astylus bar,

spaced arms carried by the sound box and arms being arranged on oppositesides of the stylus barandin the same plane, the.

other '7 arm being positioned between the through the points is parallelto the plane of the dia- V plane of the diaphragm o'f the sound box.

' the outer outer arms in a diiferent but parallel plane,

opposed arms on the stylus bar arranged adacent the outer arms on thesound box, plns adyustably arranged between the outer arms allel withthe axesrfi the pins and coaeting with the stylus bar and the medial armand acting in opposition to the pins whereby the armsor the stylus barare permitted to osoillate freely and eonvey'the vibrationsimpa-rterltothe stylus, with aminimum resistance, to the diaphragm, andthe points of engagement: of the pins and bearing member being arrangedin the same plane and in aligninent'with eachiother so that a line drawnthrough the points is parallelto the *In testimony whereof he hasaflixed his signature in presence of two Witnesses.

* FREBRX CK'ALFRED EDWARD JENKINS. Witnesses: m I r T. C. ALLEN,WfALLEN}

